U.S. Secretary of State John Kerry meets with Afghan President Hamid Karzai, left, and Pakistani Army Chief Gen. Asfhaq Parvez Kayani (right) on April 24 in Brussels, Belgium. The meeting was to discuss regional security issues, and the withdrawal of NATO forces from Afghanistan. (Evan Vucci/AP)

BRUSSELS — After meeting for more than three hours here Wednesday with Afghan and Pakistani leaders, Secretary of State John F. Kerry reported progress in relaunching negotiations but warned, “We’re not going to raise expectations or promise results that can’t be delivered.”

Instead, Kerry said before boarding a plane to return to Washington, the leaders agreed to “underpromise but deliver.”

“We’re all going to go home and do our homework,” he said, flanked by Afghan President Hamid Karzai and Gen. Ashfaq Kayani, Pakistan’s army chief. The trio had eaten lunch together and walked the grounds of a secluded estate outside Brussels as part of their meeting.

Karzai and Kayani, who had eyed each other warily at the beginning of the session, standing stiffly before a row of reporters, shook hands warmly at the end. Kerry promised that they would continue the dialogue in hopes of finding a way to work together on peace negotiations with the Taliban.

“We agreed we are committed to try to find stability and peace for both countries and the region,” Kerry said. “I think we’re on a good track,” he added, but “results will tell the story.”

Obama administration officials, who have long said that a negotiated settlement with the Taliban was the only way to truly end the Afghanistan war, see the window for talks closing. Kerry called “the road forward” a “crucial transformation period.”

The Taliban walked out of preliminary talks with the United States more than a year ago, alleging bad faith in negotiations over a possible prisoner swap in which five Taliban detainees at Guantanamo Bay, Cuba, would be released in exchange for Sgt. Bowe Bergdahl, the U.S. soldier held by the group in Pakistan since 2009.

With this year’s fighting season well underway, U.S. intelligence officials think that the Taliban’s senior, Pakistan-based leaders and its ground commanders inside Afghanistan are divided over whether to wait out the U.S. departure or to join the Afghan political process in hopes of winning influence at the ballot box next year.

Afghanistan has accused Pakistan of playing a double game, saying publicly that it favors talks between the Taliban and Karzai’s government while privately keeping the Taliban leadership on a tight leash to prevent the negotiations from getting off the ground.

Pakistan insists that it does not control the Taliban. But it fears that post-withdrawal chaos next door will undermine its security and wants to preserve its leverage over events in Afghanistan.

The Obama administration has tried for several years to bring the two governments together in tripartite talks. Although there has been some progress, with an increase in cross-border trade and pledges of further cooperation, both sides remain mutually suspicious and occasionally hostile.

Pakistan accuses Afghanistan and the U.S. military of failing to pursue members of the Pakistani Taliban, a separate group that it says has sanctuaries on the Afghan side.

A Pakistani agreement to host a meeting between top religious leaders from both countries remains unfulfilled. Pakistan holds a number of top Taliban leaders in detention and agreed, in earlier U.S.-sponsored talks, to release them to Afghanistan’s High Peace Council so they could participate in peace talks. Although some were released late last year, U.S. and Afghan officials said they were not placed in official Afghan hands but were simply let go. Those Taliban members at the top of the Afghan list remain in Pakistani custody.

The border between the two countries has long been disputed, and Afghanistan does not recognize the Durand Line drawn by the British last century. This month, Karzai angrily alleged encroachment when Pakistan constructed a border gate in mountainous territory that he insisted belongs to Afghanistan. Hundreds of Afghan students in the city of Jalalabad, near the frontier, demonstrated and shouted anti-Pakistan slogans.

The Obama administration is juggling its relationships with both governments. Kerry, who interacted with senior Afghan and Pakistani leaders for years as a member of the Senate Foreign Relations Committee, clearly hoped his participation in Wednesday’s talks would break the ice.

“We are going to have a trilateral and try to talk about how we can advance this process in the simplest, most cooperative, most cogent way, so that we wind up with both Pakistan’s and Afghanistan’s interests being satisfied — but, most importantly, with a stable and peaceful Afghanistan,” Kerry told diplomats Tuesday at a NATO meeting here at which the alliance discussed its plans for withdrawal from the country in 2014.

Karzai also used that meeting as an opportunity to invite the participation of Kayani, who maintains tight control over Pakistan’s foreign and defense policies.

Pakistan has only a transitional government at the moment, with elections scheduled for next month. Although there is no foreign minister in place, Kayani was accompanied by Foreign Secretary Jalil Abbas Jilani.

Karen DeYoung is associate editor and senior national security correspondent for the Washington Post.

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